In order to write data to and read data from a media, a recording head is typically used. FIG. 1 depicts a conventional perpendicular magnetic recording (PMR) head 10 that includes a read transducer 12 and a conventional write transducer 14. For clarity, FIG. 1 is not drawn to scale. Although both the conventional read transducer 12 and the conventional write transducer 14 are shown, the conventional write transducer 14 may be part of a head that only performs writing. In addition, the conventional PMR head 10 may also include a slider (not shown).
The read transducer 12 includes a first shield (S1) 15, a read sensor 16, and a second shield (S2) 18. The conventional PMR write transducer 14 includes a first pole 20 that may be separate from the S2 18, a first coil 22, a metal underlayer 23, a conventional PMR pole 24, a second pole (P2) 26, an insulating space 28, a write gap 30, a conventional shield 32 that may include portions 32A and 32B, and a second coil 34. The conventional shield 32 perpendicular to the ABS that is on the order of thirteen to sixteen micrometers. The nonmagnetic metal underlayer 23 may be used under the conventional PMR pole 24 to improve manufacturability of the conventional PMR pole 24. As a result, the conventional P2 26 resides on top of the conventional PMR pole 24. Although not explicitly shown, seed layer(s) may be used in providing the conventional poles 22, 24, and 26. The conventional PMR write transducer 14 is also depicted with two coils 26 and 34. However, PMR heads having a single coil are also typically used. In addition, the throat height (TH) and shield height (SH) are also shown.
In order to write data to a PMR media, the coils 26 and 34 are energized. Consequently, the conventional P2 26 and conventional PMR pole 24 are magnetized and the media written by flux from the pole tip of the conventional PMR pole 24. Based on the direction of current through the coils 26 and 34, the direction of magnetic flux through the conventional PMR pole 24 changes. Thus, bits having opposing magnetization can be written and the desired data stored on the PMR media.
Although the conventional PMR head 10 functions, there may be drawbacks, particularly in adapting the conventional PMR head 10 to higher densities. In particular, the conventional PMR head 10 may have poor write efficiency at hither densities. In the conventional PMR head 10, the P2 26, or yoke, is at the top of the conventional PMR pole 24. The insulating spacing 28 that separates P2 26 from the shield portion 32A typically has a depth, d, of at least one micron. This depth is sufficient to ensure that the fabrication of the conventional PMR head 10 may be performed with sufficient process margins. For example, the P2 26 and shield portion 32A may be formed from the same material and at the same time. The insulator 28 might be formed by removing a portion of this material, refilling using an insulator, and performing a planarization. In order to ensure that this can be accomplished with sufficient yield, the P2 26 is placed at least one micron from the back of the shield portion 32A. Stated differently, the depth, d, is at least one micron. When the conventional PMR head 10 is scaled to higher densities, the thickness of the poles 24 and 26 may be reduced. Despite its reduced thickness, the P2 26 is still spaced from the back of the shield portion 32A by at least one micron. As a result, the write efficiency of the conventional PMR head 10 may be reduced.
Accordingly, what is needed is a system and method for improving the write efficiency of a PMR head, particularly at higher densities.